U.S. patent number 11,453,570 [Application Number 16/172,311] was granted by the patent office on 2022-09-27 for elevator communication arrangement.
This patent grant is currently assigned to KONE CORPORATION. The grantee listed for this patent is KONE Corporation. Invention is credited to Antti Hovi, Ari Kattainen.
United States Patent |
11,453,570 |
Kattainen , et al. |
September 27, 2022 |
Elevator communication arrangement
Abstract
Conventionally, elevator communications have been implemented
using travelling cables. This is particularly the case when safety
related data transmitted from an elevator car has to fulfil
real-time restrictions often set by regulators so that the
receiving of the information may not be delayed. Typically, this
cannot be guaranteed when wireless transmission technologies are
used. The reliability can be increased by using a second to
supplement the wireless transmission.
Inventors: |
Kattainen; Ari (Helsinki,
FI), Hovi; Antti (Helsinki, FI) |
Applicant: |
Name |
City |
State |
Country |
Type |
KONE Corporation |
Helsinki |
N/A |
FI |
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Assignee: |
KONE CORPORATION (Helsinki,
FI)
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Family
ID: |
1000006587024 |
Appl.
No.: |
16/172,311 |
Filed: |
October 26, 2018 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190062103 A1 |
Feb 28, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/FI2017/050377 |
May 18, 2017 |
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Foreign Application Priority Data
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May 20, 2016 [EP] |
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16170587 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B66B
13/22 (20130101); B66B 1/3453 (20130101); B66B
1/3446 (20130101); B66B 5/0031 (20130101); B66B
1/48 (20130101) |
Current International
Class: |
B66B
1/34 (20060101); B66B 13/22 (20060101); B66B
5/00 (20060101); B66B 1/48 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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101279686 |
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Oct 2008 |
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CN |
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104876076 |
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Sep 2015 |
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CN |
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1 864 934 |
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Dec 2007 |
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EP |
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2 062 842 |
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May 2009 |
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EP |
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2004-26433 |
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Jan 2004 |
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JP |
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WO 2016/051012 |
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Apr 2016 |
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WO |
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Other References
European Search Report for EP 16 17 0587, dated Nov. 24, 2016.
cited by applicant .
International Search Report issued in PCT/FI2017/050377
(PCT/ISA/210), dated Sep. 5, 2017. cited by applicant .
Written Opinion of the International Searching Authority issued in
PCT/FI2017/050377 (PCT/ISA/237), dated Sep. 5, 2017. cited by
applicant.
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Primary Examiner: Donels; Jeffrey
Attorney, Agent or Firm: Birch, Stewart, Kolasch &
Birch, LLP
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of PCT International Application
No. PCT/FI2017/050377, filed on May 18, 2017, which claims priority
under 35 U.S.C. 119(a) to patent application Ser. No. 16/170,587.6,
filed in Europe on May 20, 2016, all of which are hereby expressly
incorporated by reference into the present application.
Claims
The invention claimed is:
1. A method for transmitting safety related information from an
elevator car comprising the steps of: receiving, at a communication
module, safety related information from at least one device
producing safety related information; transmitting said received
information as a first signal by a first wireless transmitter;
producing a second signal based on said received information; and
transmitting said second signal by a second wireless transmitter,
wherein the step of transmitting said second signal is performed
using transmission over a wireless energy channel by the second
wireless transmitter.
2. The method according to claim 1, further comprising the step of
transmitting said second signal using an optical transmitter.
3. The method according to claim 1, wherein the second wireless
transmitter has a different configuration from the first wireless
transmitter.
4. The method according to claim 1, further comprising the step of:
determining an interruption of both the first signal and the second
signal; and as a response to the determined interruption,
increasing a counter and preventing the operation of the elevator
in case that the counter reaches a predetermined threshold
value.
5. A computer program embodied on a non-transitory computer
readable medium, wherein said computer program is configured to
perform the steps of claim 1, when executed in a computing
device.
6. A method for transmitting safety related information from an
elevator car comprising the steps of: receiving at a communication
module, safety related information from at least one device
producing safety related information; transmitting said received
information as a first signal by a first wireless transmitter;
producing a second signal based on said received information; and
transmitting said second signal by a second wireless transmitter,
wherein the method further comprises the step of producing said
second signal by reducing information from said first signal.
7. The method according to claim 6, wherein transmitting said
second signal using an optical transmitter.
8. A method for transmitting safety related information from an
elevator car comprising the steps of: receiving, at a communication
module, safety related information from at least one device
producing safety related information; transmitting said received
information as a first signal by a first wireless transmitter;
producing a second signal based on said received information; and
transmitting said second signal by a second wireless transmitter
only after an interruption of the first signal has been
detected.
9. An elevator comprising the apparatus according to claim 8,
wherein said apparatus is located in an elevator car.
10. The elevator according to claim 9, wherein said elevator
further comprises receivers configured to receive said first and
second signals, wherein said receivers are located in an elevator
shaft of the elevator.
11. An elevator according to claim 9, wherein the elevator
comprises a plurality of elevator cars in one elevator shaft.
12. An apparatus comprising: at least one data communication
interface configured to receive an incoming signal comprising
safety related information; at least one processor configured to
execute computer programs; at least one memory configured to store
said computer programs and data; a first wireless data transmitter
configured to transmit a first signal, wherein said first signal is
in accordance with said received incoming signal; and a second
wireless data transmitter configured to transmit a second signal,
wherein said second signal is based on said received incoming
signal, wherein said second wireless data transmitter is a
transmitter using a wireless energy charging channel.
13. The apparatus according to claim 12, wherein said at least one
data communication interface comprises a serial port according to
RS485 specification.
14. The apparatus according to claim 12, wherein the first wireless
data transmitter is a wireless local area network transmitter.
15. The apparatus according to claim 12, wherein said second
wireless data transmitter is an optical transmitter.
16. The apparatus according to claim 14, wherein said second
wireless data transmitter is similar to said first wireless data
transmitter, hut configured to use different transmission
parameters.
Description
DESCRIPTION OF BACKGROUND
The following description discloses an arrangement for data
communications in an elevator. Particularly the arrangement is
related for a transmission of safety critical information.
Elevator safety has been a critical issue for a long time.
Elevators are equipped with a plurality of devices and apparatuses
that are used to improve the passenger safety. One very traditional
way of implementation is a safety circuit, wherein a possible
defect is determined if the circuit is not closed. For example,
when an elevator car arrives at a floor the doors are opened for a
predetermined moment. The state of the safety circuit is changed
into open state when the doors are opened. This may be done, for
example, by using one or more safety switches in the door
arrangement. When the door is closed the safety switches again
change their state and indicate that the doors are closed. However,
if the doors are not properly closed the partially open door can
cause a potentially dangerous situation and the operation of the
elevator should be prevented. Safety switches in the door are just
an example and an elevator car may and typically comprises more
safety switches and safety related devices. Furthermore, some
devices or a portion of the related safety circuit may be located
outside of the elevator car. For example, a typical elevator door
comprises door leaves in the elevator car and in the floor side
similar door leaves or a hinged conventional door that should be
locked when the elevator is not behind the door.
Conventionally the information from the safety circuit to the
controller controlling the elevator and the movement of the
elevator car is transmitted using a travelling cable. In many cases
the transmission is done in serial form, for example, by using
RS485 transmitters and receivers. Transmissions are typically
scheduled so that information related to safety devices is received
in accordance with tight real time requirements. In some
embodiments the receiving of the information is implemented so that
it is dependent on the scheduling and needs to be synchronized. A
drawback of this approach is that when the buildings are higher the
need for bandwidth is increased, however, the longer travelling
cable is the lower the bandwidth of the cable is.
In high buildings and in some special installations, such as marine
vessels, the cables are also prone to defects because of movement
caused by wind or other reasons. In case of inclined elevators
there may be other problems in providing an installation.
As can be seen from the issues mentioned above there is a need for
replacing the travelling cable as a transmission medium. However,
the new transmission medium must fulfill the requirements that are
often set by regulatory bodies. A further problem is that in
replacement installations the new transmission medium should be
compatible with other components of the old installation using
travelling cable at the same time as fulfilling the
requirements.
SUMMARY
An elevator communication arrangement is disclosed. Conventionally
elevator communications have been implemented using travelling
cables. This is particularly the case when safety related data
transmitted from an elevator car has to fulfil real-time
restrictions often set by regulators so that the receiving of the
information may not be delayed. Typically this cannot be guaranteed
when wireless transmission technologies are used. The reliability
can be increased by using a second to supplement the wireless
transmission.
In an embodiment a method for transmitting safety related
information from an elevator car is disclosed. In the method a
communication module receives safety related information from at
least one device producing safety related information. The received
information is then sent as a first signal by a first wireless
transmitter. Then a second signal based on the received information
is produced. The second signal is then sent by a second wireless
transmitter.
In an embodiment the second signal is produced by reducing
information from the first signal. In an embodiment the first
transmitter used is an ordinary wireless data communication
transmitter. In an embodiment the transmitter used to transmit the
second signal is an optical transmitter. In another embodiment the
second transmitter is a transmitter transmitting over a wireless
energy channel. In another embodiment the second signal is
transmitted using a similar transmitter as for the first signal. In
a further embodiment the transmitter of for the second signal has
different configuration settings.
In a further embodiment the method disclosed above using mentioned
transmitters is implemented as a computer program. When the
computer program is executed in a computing device it is configured
to perform the steps discussed above.
In another embodiment an apparatus comprising at least one data
communication interface configured to receive incoming signal
comprising safety related information, at least one processor
configured to execute computer programs, at least one memory
configured to store the computer programs and data, a first
wireless data transmitter configured to transmit a first signal,
wherein the first signal is in accordance with received incoming
signal and a second wireless data transmitter configured to
transmit a second signal, wherein the second signal is based on the
received incoming signal, is disclosed.
In an embodiment at least one data communication interface
comprises a serial port according to RS485 specification. In an
embodiment the first wireless data transmitter is a wireless local
area network transmitter. In an embodiment the second wireless data
transmitter is an optical transmitter. In an embodiment the second
wireless data transmitter is a transmitter using a wireless energy
charging channel. In an embodiment the second wireless data
transmitter is similar to the first wireless data transmitter
configured to use different transmission parameters.
In an embodiment an elevator comprising an apparatus discussed
above is disclosed. In an embodiment the elevator further comprises
receivers configured to receive the first and second signal,
wherein the receivers are located in the elevator shaft.
A benefit of an elevator communication arrangement disclosed above
is that the use of travelling cables can be avoided. This leads
into savings because the weight of ropes is reduced. Furthermore,
as the number of ropes is reduced it is possible to produce simpler
solutions. A further benefit of the elevator communication
arrangement described above is that the need for maintenance is
reduced because travelling cables that are sometimes prone for
defects do not need to be replaced. The replacement procedure is
complicated and expensive. A further benefit of the elevator
communication arrangement disclosed above is that the arrangement
can be easily used in new and old installations. When the elevator
communication arrangement disclosed above is used as a replacement
in old installations a benefit of the arrangement is that it does
not require any further changes to other devices or parts in the
elevator system. Thus, the devices that are receiving transmissions
can be used without changes.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further
understanding of the elevator communication arrangement and
constitute a part of this specification, illustrate embodiments and
together with the description help to explain the principles of the
elevator communication arrangement. In the drawings:
FIG. 1 is a block diagram of an example embodiment of the present
elevator communication arrangement;
FIG. 2 is a block diagram of an example embodiment of the present
elevator communication arrangement;
FIG. 3 is a flow chart of a method according to an example
embodiment of the present elevator communication arrangement;
and
FIG. 4 is an example of an elevator using the present elevator
communication arrangement.
DETAILED DESCRIPTION
Reference will now be made in detail to the embodiments, examples
of which are illustrated in the accompanying drawings.
In FIG. 1 a block diagram of an elevator communication arrangement
is disclosed. In the example of FIG. 1 a conventional traction
elevator comprising an elevator car 10, counterweight 11, at least
one rope 12 and traction sheave 13 are disclosed. In the figure at
least one rope 12 is assumed to represent all ropes that the
elevator needs. Thus, these ropes may include a rope used for
communications that should be replaced because of a defect. Even if
the example of FIG. 1 discloses a conventional elevator using a
counterweight also other arrangements may be used, for example,
elevators without counterweight, elevators having an inclined
elevator shaft or any other type of elevators that use a travelling
cable for data transmissions.
In the example of FIG. 1 the elevator car 10 comprises a time
triggered safety module 14. The purpose of the module is to collect
the needed data and transfer it further. In the example of figure
the time triggered safety module is configured to send the
collected safety information using predetermined intervals over an
RS485 connection. RS485 is just an example and other wired
connection types may be used instead.
The elevator car 10 further comprises a communication module 15
that is configured to receive the information over an RS485
connection. The communication module is configured to transmit the
received information to a receiver 16 that is located at the top of
the elevator shaft. In the example also a second transceiver 17 is
disclosed. The received 17 represents a floor level receiver and
similar receiver may be located in each of the floors where the
elevator car 10 can stop. Furthermore, even if it is not shown in
the figure a person skilled in the art understands that a receiver
similar to receiver 16 may be located in the bottom of the elevator
shaft. In such embodiment a further transmission antenna may be
located below the elevator car 10.
The communication module 15 comprises two transmitters that will be
explained in more detail below. The transmitters are independent of
each other and the communication module 15 may be constructed of
more than one components. Furthermore, the communication module 15
comprises data communication connection for receiving information
from time triggered safety module 14. As mentioned earlier, an
example of a typical communication connection used is RS485. The
time triggered safety module 14 needs to have only one RS485
connection from which the communication module 15 receives the
information by using one receiver. The communication module 15 then
transmits the further using at least one transmitter so that the
information comprises all received data. In the following
description this transmission is called as a first signal. In
addition to the first signal a second signal is also transmitted.
The transmitter for transmitting the second signal may be similar
to the transmitter of the first signal, however, also other
transmitter types may be used. Further details will be discussed in
detail with referral to other figures.
Receivers 16 and 17 receive the transmitted information. If the
original information received was in conventional RS485 submission
the received wireless information is transformed back to the RS485
form and transmitted further using a RS485 compatible connection.
The new signal is constructed in a manner that the signal is
identical to the conventional signal transmitted over a travelling
cable. Thus, synchronization of the signal may need to be taken
into account.
In FIG. 2 an arrangement disclosing a communication module similar
to the communication module in FIG. 1 is disclosed. The
communication module 20 comprises a serial port 21 for receiving
serial communication, for example, in RS485 form. In other
embodiments there may be also other wired networking technologies
used. Examples of such are other serial port standards and wired
local area networks. The serial port 21 receives information from a
time triggered safety module similar to described in FIG. 1. The
time triggered safety module may be any commonly used time
triggered safety module and does not need to be changed for using a
communication module 20 instead of using a travelling cable. Even
if in embodiment shown in FIG. 2 only one serial port is shown
there may be two or more serial ports or similar data communication
interfaces. The data received may also be identical between two or
more different ports. Thus, the purpose two or more ports may be
the possibility to increase the data liability. However, it is also
possible that different serial ports are configured to receive data
from different safety devices.
The communication module 20 may include also more than one serial
port or other communication devices configured to receive
information from other arrangements located in an elevator car or
on a floor where the car has stopped. Furthermore, even if only
safety related data is discussed in this description the
communication module may be used also for other communications. The
communication module processes information received by the serial
port 21 by at least one processor 22. The at least one processor 22
is coupled with at least one memory 23 that is configured to store
computer program code and related data. The processor 22 is then
configured to transmit the data further.
In the embodiment of FIG. 2 a conventional wireless local area
network transmitter 24 is used as a primary transmitter. The
transmitter 24 may comprise a directional antenna, however, it is
not always necessary. The need for directional antenna and other
configuration is determined by the building conditions. For
example, a high very large building typically comprises a very
large number of existing wireless local area networks that may
cause interference that needs to be taken into account. Smaller
buildings may not need any particular configurations. Typical
configuration options include directional antenna and related
transmission parameters and choosing and/or reserving a particular
frequency for wireless communication. The signal transmitted by the
wireless local area network transmitter 24 is hereafter referred as
the first signal.
As mentioned above the signals related to safety have relatively
strict real-time needs and they need to be received at regular
intervals comprising the whole signal information. This information
is important because it determines if it is safe to operate the
elevator and it may include typically status of each safety related
component. As mentioned above the wireless communication path is
prone to delays and it is likely wireless area network transmitter
24 cannot always provide the required information on time. The
absence of the information typically leads to the prevention of the
elevator operation. The communication module 20 includes a second
transmitter 25 that is configured to transmit a second signal.
As mentioned above the first signal may and typically includes
information from various sources. The information provided in the
first signal is thus conventional data communications. The second
signal, however, may be a simpler signal informing the final result
of the message. The final result in this context is that if the
elevator is still safe to operate or not. Thus, this information
may be compressed into just one bit.
In the example of FIG. 2 the at least one processor 22 is
configured to process the information received from the serial port
21 and to determine if the elevator is safe to operate. At the same
time the first signal is transmitted by wireless local area network
transmitter 24. The processor 22 also further transmits the
information to the second transmitter 25.
In the example of FIG. 2 the second transmitter 25 is a structured
light transmitter, for example a laser device. The second
transmitter 25 may be configured to transmit light to the
counterpart receiver when the elevator is safe to operate. When the
elevator car stops on a called floor the doors will open. Thus, the
safety switches will also open and indicate that the elevator
cannot operate at the moment. Correspondingly the secondary
transmitter 25 will not transmit light when the doors are open.
When the doors close also the safety circuit indicates that doors
have been closed and the light is again transmitted. If the doors
won't close because a defect the light will not be transmitted.
Thus, even in those cases when the first signal is not received
appropriately the operation of the elevator can be prevented. The
second signal can be transmitted continuously. Based on the second
signal the elevator can be safely driven when the first signal is
not received on time. It is possible to provide a threshold value
for the period how long the absence of the first signal is
tolerated or which events can be performed when the first signal is
not received. For example, it is possible to prevent or delay the
elevator car leaving a floor when the first signal is not present,
however, if the elevator car is already moving it may be brought to
the next called floor instead of stopping next possible floor.
The communication module 20 transmits information to a receiver
that may be similar communication module, which receives wirelessly
first and second signals, processes them and sends the information
further using a serial connection. There may be also other
connection types for transmitting the information further. For
example, the receiving communication module may be connected to
several wired and wireless network connections.
In the above a laser light was disclosed as a transmitting means
for second signal. This should be interpreted as an example only
and other means may be used.
In another embodiment the second signal is transmitted using
wireless electric transmission that is used to charge batteries
located in an elevator car in case where there is not travelling
cable for electricity. The transmission may be provided at every
floor so that when the battery is charged a low bandwidth messages
are sent over the wireless charging.
In another embodiment the second signal is sent using transmission
means similar to the first signal. Thus, two separate wireless
local area network transmitters may be used. The first and second
signal may be in this case identical but they are transmitted with
different parameters, such as transmission frequency. In another
embodiment the second signal is binary signal as in case of light
but is transmitted using similar transmitter as for the first
signal. In a further embodiment the second signal is a reduced set
of information comprised in the first signal, however, the signal
is not a binary signal. The reduced signal and binary signal
require less bandwidth and they may be in some cases transmitted
successfully when the first signal is not received in time.
FIG. 3 discloses of a method according to an embodiment. The method
may be, for example, be implemented in a device similar to FIG. 2,
wherein the device comprises at least two separate transmitters and
at least one receiver for receiving safety related
transmissions.
The method is shown in sequential steps, however, it may include
parallel steps as explained below. Furthermore, all steps shown in
FIG. 3 may be continuous processes through which the received data
travels. Thus, the method is initiated when new data arrives at the
receiving port and a serial transmission is received, step 30.
The transmission is then processed, step 31, so that the
information needed for transmitting is acquired. For example, the
processing includes determining that the serial transmission is
complete and can be sent further. The processing may also alter the
received data transmission in order to meet the requirements of the
final receiver. This may be the case if some components have been
changed during sometimes very long life of an elevator and the
devices are not compatible anymore. However, it is also possible
that the processing includes only forwarding the received
transmission to the first transmitter, which is typically a
wireless local area network transmitter, possibly with directional
antenna, that is configured to act as a bridge in serial
transmission. Then the first transmitter transmits the signal, step
34.
The same signal also forwarded to further processing. In case of
FIG. 3 this includes producing a second signal that is based on
information submitted in the first signal. In a very simple
implementation where an optical transmitter, such as a laser, is
used, the content of information may be reduced into a one bit.
Thus, if the information comprised in the first signal indicates
that the elevator can be operated a bit indicating that the
elevator is in order is sent. In case of problems a bit indicating
that the operation is not safe is sent. The content of the bit may
be freely chosen, for example 0 may indicate that there is no
problems and 1 may indicate problems. The information needs not to
informed only one bit but also two or more bits may be used,
however, the used transmitters may have limited bandwidth and
reduced information is typically preferred. Furthermore, the
purpose of the second signal is to supplement the first signal and
not to replace it. Thus, if the first signal is not received for a
long period a maintenance may be required and based on suspected
defect the operation may be prevented.
Lastly the second signal is transmitted, step 33. Even if signal
are independent they are sent substantially at the same time. There
is no synchronization requirement between these two signals. The
information sent from the communication module is then received at
receivers that are located in an elevator shaft. The receivers may
be, for example, at the top of the shaft, at the bottom of the
shaft or both. These receivers are configured to receive the
transmissions wirelessly and transmit them further, for example, by
using a serial transmission in accordance with RS485 or other
transmission types.
In FIG. 4 an example of an elevator using an elevator communication
arrangement is disclosed. In FIG. 4 an elevator with multiple
elevator cars 31a-31c running in the same elevator shaft 30 is
disclosed. There are several possibilities for implementing such an
elevator. For example, the elevator cars may be connected so that
they always move at the same time in the same shaft. In another
implementation there are separate downward and upward shafts in
which the elevators move independently, however, naturally taking
the movements of other elevator cars into account as one car cannot
overtake another.
Elevator cars 31a-31c comprise a communication module 32a-32c,
which may be similar to the communication module of FIG. 2.
However, in the example of FIG. 4 it is not possible always to use
optical communication means as laser beam, infrared beam or similar
optical beam cannot pass through the elevator car between the
transmitter and receiver. Thus, radio transmission based
technologies, such as wireless local area network or similar must
be used.
In the example of FIG. 4 communication modules 32a-32c include two
similar wireless local area transmitters that are commonly
available for data communication purposes and capable of
bidirectional data transfer. In FIG. 4 only one receiving module 33
is disclosed, however, when the elevator shaft is high there may be
more than one receiving module configured to receive from
communication modules 32a-32c. The receiving module 33 may be a
communication module comprising two separate wireless local area
network receivers. When two separate wireless local area network
receivers are used the communication settings may be different. In
such case transmitters and receivers are used as pairs. Thus, the
first transmitter of communication modules 32a-32c are configured
to communicate with the first receiver of receiving module 33 and
the second transmitter of communication modules 32a-32c are
configured to communicate with the second receiver of the receiving
module 33.
When the transmitters and receivers are organized in pairs they may
configured to use different frequencies or channels so that even if
the transmitters may be technically identical they are operated
with different settings in order to improve the communication
reliability. If either of the pairs fail the other may still be
operational.
In the example of FIG. 4 the transmitters are similar to each other
but using different channels. Furthermore, they are configured to
transmit identical information. Optionally it is possible to
configure the second transmitter to transmit a reduced signal as
described above with regard other examples.
The examples described above may be provided with a counter
counting the number of unsuccessful transmissions. For example, it
is possible to set a threshold of three transmissions so that the
elevator is stopped only after the threshold of unsuccessful
transmissions is reached. The counter may be configured such that
it is counting occurrences when transmissions by both (or all if
more than two) transmitters fail. This can be done, for example, by
using a counter device or counter program at the receiver side.
When both first and second signal are not received the counter is
increased until a threshold is reached. If the threshold is reached
the operation of the elevator will be prevented. The counter is
reset if the first or second signal is again received normally.
Thus, if the threshold is set to three, both of the signals may be
interrupted once or twice in a row and the operation of the
elevator may still be continued.
In a further embodiment the second signal is sent only after the
interruption of the first signal is detected. The detection may be
based, for example, on predetermined transmission pattern or
monitoring acknowledgement messages. If a counter is used for
allowing a predetermined number of interrupted transmissions the
counter is increased only after the interruption of the second
signal is detected. The counter is reset if either the first or
second signal is received correctly. The second signal may be
reduced ok-to-run type of signal or an identical copy of the first
signal.
The above described method may be implemented as computer software
which is executed in a computing device able to communicate with
external devices. When the software is executed in a computing
device it is configured to perform the above described inventive
method. The software is embodied on a computer readable medium so
that it can be provided to the computing device, such as the
communication module 20 of FIG. 2.
As stated above, the components of the exemplary embodiments can
include computer readable medium or memories for holding
instructions programmed according to the teachings of the present
embodiments and for holding data structures, tables, records,
and/or other data described herein. Computer readable medium can
include any suitable medium that participates in providing
instructions to a processor for execution. Common forms of
computer-readable media can include, for example, a floppy disk, a
flexible disk, hard disk, magnetic tape, any other suitable
magnetic medium, a CD-ROM, CD.+-.R, CD.+-.RW, DVD, DVD-RAM,
DVD.+-.RW, DVD.+-.R, HD DVD, HD DVD-R, HD DVD-RW, HD DVD-RAM,
Blu-ray Disc, any other suitable optical medium, a RAM, a PROM, an
EPROM, a FLASH-EPROM, any other suitable memory chip or cartridge,
a carrier wave or any other suitable medium from which a computer
can read.
It is obvious to a person skilled in the art that with the
advancement of technology, the basic idea of the elevator
communication arrangement may be implemented in various ways. The
elevator communication arrangement and its embodiments are thus not
limited to the examples described above; instead they may vary
within the scope of the claims.
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